Steam-boiler



(No Model.)

H. SPENCE.

STEAM BOILEB..

Patented Mar. 16, 1886.

. lill ooooooooooo 0,0ownmmmmmmn@U.. oooooooooooo ooooooooooo .w "HHIY lm 1 m 1 m r N .ANN

UNITED STATES PATENT OFFICE.

HAMILTON SPENCE, OF MINNEAPOLIS, ASSIGNOR OF ONE-HALF TO DENZEL W.DAVIS, OF HASTINGS, MINNESOTA.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 338,1l3 dated March 16I1886.

Application filed June 6, 1885. Serial No. 167,902. (No model.)

To @ZZ whom it may concern.-

Beit known that I, HAMILTON SPENCE, a citizen of the United States,residing at Minneapolis, in the county of Hennepin and State ofMinnesota, have invented certain Improvementsin Steam-Boilers, of whichthe following is a specification.

My invention relates more particularly to improvements in locomotiveboilers, though applicable to any horizontal boilers; and the objects ofmy invention are to obtain a nearly perfect combustion of the soft coalor wood used as fuel, and, by drawing the products of combustion awayfrom the furnace through the tubes of the boiler at a less rapid ratethan is usually done, to radiate more heat from the tubes to the waterin the boiler, and at the same time to lessen the injury to the tubes;to increase the steam-producing qualities of the boiler by introducingthe feed-water at the point where the heat makes its final exit from theboiler 5 to provide a separate settlingchamber in the boiler.

To the above ends my invention consists in the construction andcombination of devices hereinafter described, and particularly pointedout in the claims.

In the accompanying drawings, Figure lis a longitudinal section of alocomotive-boiler embodying my invention. Fig. 2 is-a section on line.fr :t of Fig. l. Fig. 3 is a longitudinal section on line 1/ yof Fig.l. Fig. 4 is a detail view showing the manner of applying a part of myimprovements to an ordinary boiler.

In the drawings, A represents the shell of the boiler. B represents thefire-box; C, the grate; D, the ash-pan; E, the lower portion of thesmoke-stack, and J the smoke-box. The shell of the boiler preferablytapers, being slightly greater at the back tube-sheet than at theforward tube-sheet, for a purpose hereinafter stated. A horizontalpartition, F, eX- tends from the back tube-sheet nearly to the forwardtube-sheet, being secured in position by any suitable means. Thispartition has also a suitable extension passing to the mudring betweenthe walls of the fire-box and the shell of the boiler, preferably onabout the 5o line of the arch K.

G represents a series of directtubes extending through the boiler' abovethe partition F, and H represent-sia series of return-tubes extendingthrough the boiler below the partition F. The exit ends of tubes H openinto a space between the back tube-sheet and a cast-iron lining, I.

K represents an arch, formed, preferably, as a water-leg, attached tothe back tube-sheet immediately above the partition F, the taper 6c inthe boiler affording sufficient space for the water-leg between thepartition and the lower row of tubes, G. This water-leg extends to theash-pan D, and has a number of tubes, k, extending through it andopening into the lire-box. The upper end of the lining I fits closelyunder the curved part of the arch K. The feed-pipe a opens into theboiler below partition F and near the exit end of the returniues H. 7

L represents a suction-fan, arranged,prefer` ably, beneath the shell ofthe boi-ler, and connected by a pipe, L', with the space back of thelining I. From this fan extends a second pipe, L2, that opens into theash-pan D be- 7` neath grate C. A vertical pipe, L3, branches off frompipe L, and a damper, Z, is arranged at the lower end of pipe L, so thatit may either close that pipe or may be swung into a vertical positionto close the pipe Ll. S

M represents a blast-fau, that is also preferably arranged beneath theshell of the boiler, and is provided with a pipe, M', that opens intothe ash-pan D.

d represents a hinged damper arranged to 8 either close or partiallyclose the opening into the ash-pan, and e is a damper in the lower endof the smoke-stack.

O represents the forward part of the leg of the boiler. g P representsthe exhaust-steam pipe in the smoke-box.

The fan-blower M introduces a supply of fresh air to the ashpan, fromwhich it passes through the grate C and the arch K to the g fire-box,thereby furnishing the oxygen necessary for the combustion of the fuel.The products of combustion pass from the fire-box through the upper ordirect ues into the vsmoke-box J, from which they are drawn by 1 the fanL through the lower or return flues, II, and pipe L Vto the fan. Fromthe fan they pass into the pipe L2. Zhen the pipe L' is closed by damperZ, they pass into the exitpipe L3 and are discharged. Vhen the pipe L isclosed by damper Z, the products of combustion are passed through thepipe L2 into the ash-pan, where they mingle with the air from the fan Mand pass into the fire-box, where all. of the combustible gases areconsumed.

In burning soft coal and wood,whenever a fresh supply of fuel is addedto the fire, a large amount of black smoke is thrown out from thechimney or smoke-stack, and this is more especially so when the fuel isthrown in on top of the fire in the furnace or smoke-boX.

In using` this boiler, the dampersc and Z being closed, when a freshsupply of fuel is added, the smoke and unconsumed gases are drawnthrough the return-tubes H and introduced to the ash-pan, and beingpassed into the tire-box with the air from fan M they come in contactwith the incandescent fuel, and all ofthe combustible gases areconsumed. After the fan has been operated in this manner for a time thepipe L"s is opened, and the carbonic-acid gas is drawn out and expelledfrom the furnace. VhiIe the fan L is being operated to return theproducts of combustion to the ash-pan, if the damper d be partiallyopened, a portion of the carbonic-acid gas returned to lhe ash-pan will,owingtoits greater spccic gravity, settle to thelower part of theash-pan and pass out through the damper d, from which it may beconducted by any suitable means. The fan M supplies the air necessaryfor combustion, as stated, but it is necessary to use in additionthereto some means for drawing off the products of combustion. It isusual in operating boilers of this class to exhaust the steam into thesmokeboX, and thereby to create a strong draft that draws the productsof combustion from the furnace, and draws the air necessary forcombustion through the ash-pan and the fuel on the grate. In order thatthe latter result may be obtained, it is necessary that the draftcreated be very strong; and this strong draft carries oiffrom thefurnace a large amount of unconsumed combustible gases. To avoid thisImake use of the fan M for introducing air to the re-box, but do notcreate a blast strong enough to drive off the products of combustion.For the latter purpose I provide means for creating a suction throughthe boiler-tubes that is suiiicient to draw oft' the products ofcombustion, but not enough to affect the draft of the furnace. I havedescribed the fan Las a preferable means for this purpose. In someinstances it may be desirable to use other means for this purpose. Inthe construction shown the damper c may be opened, and then byexhausting steam through the pipe P the products of combustion will bedrawn off bythe suction created. 1 In either instance,

whether the fan or the exhaust be used to remove the products ofcombustion, the suction created is just sufficient to draw off theproducts of combustion.

When the steam-exhaust is used instead of fan L, the return-iiues I-Iwill not be used but a portion of the lining I is constructed to turn ona pivot, forming a damper, t', that Inay be turned to a horizontalposition, as shown in Figs. l and 4. Apart of the products of combustionwill then pass through the openings k in the arch K, and through theopening in lining I, and then through the tubes H, which then serve asdirect tubes. The feed-water enters the boiler at a point near the exitend of the tubes H, where the heat is least, and the water passes alongthe lower compartmentvof the boiler and enters the upper compartment atthe opposite end of the horizontal partition F, and then passes along inthe upper compartment, its course from the point where it enters theboiler being in the opposite direction from the course of the productsof combustion in the tubes of the boiler, and thereby the water in thelower compartment becomes first gradually heated before it mingles withthe highly-heated water in the upper compartment. The lower compartmentforms a settling-chamber, in which all scale-forming impurities areprecipitated and deposited, so that incrustation of the boiler isprevented. The water in the lower compartment is heated hot enough topart with all foreign matter held in solution, and as in this part ofthe boiler the tubes are not hot enough to pick it up and burn it ontothem, it is deposited in the bottom of the boiler in the form ofsediment, from which it can be blown out in the usual way.

In Fig. 4t I have shown an ordinary form of boiler and the manner ofapplying the fanblowers thereto. In this instance the arch K is formedof brick, and has openings k, as in the other construction. rlhe tubesbelow the top of the arch serve as return-flues, and the fans areconnected with these tubes andwith the ash-pan, as in the constructionshown in Fig. l.

The partition F may be used or not, and when this form of arch isemployed the shell of the boiler may be cylindrical.

The motion of the fans will preferably be obtained from a separateengine employed for that purpose, so that their motion will beindependent of the motion of the main engine.

I claim as my inventionl. The combination, in a boiler, with the fan Mand a pipe extending from said fan to the ash-pan, whereby air isconstantly supplied beneath the grate, of the fan L, means connectingsaid fan with the smoke-box, a

ICO

IIO

pipe, L2, extending from said fan to the ashpan, a pipe, L3, and adamper, Z, arranged to close either the pipe L3 or the pipe L2, where bythe products of combustion are returned beneath the grate and mingledwith the air supplied byfan M, or are discharged through the pipe L3,all substantially as described,and for the purpose set forth.

2. The combination, in a boiler, with the direct tubes G and thereturn-tubes H, located below said direct tubes, of the fan L and meansconnecting said fan with the exit ends of said return-tribes, allsubstantially as described.

3. The combination, in a boiler, with the direct tubes G and thereturn-tubes H,located below said direct tubes, of the fan L, meansconnecting said fan with said return-tubes, a pipe, L, connecting saidfan with the ash-pan D, the pipe L3, and damper Z, said damper beingarranged to close either the pipe L2 or the pipe L3, all substantiallyas described, and for the purpose set forth.

4. The combination, in a boiler, with the ash-pan, fire-box, and fluesthereof, of a fan, L, means connecting said fan with the fines, a pipe,L2, connecting said fan with the ashpan, a pipe, L3, and damper l, saiddamper being arranged to close either the pipe L2 or the pipe L, wherebythe products of combustion are drawn from the boiler-dues and returnedto the ash-pan or discharged through pipe L3, substantially asdescribed.

5. rIhe combination, with the ash-pan D, having damper d, re-box B,ilues G and H, damper e, and exhaust l?, of the fan L, means forconnecting said fan with the flues H, pipes L2 and L3, damper Z, fan M,and pipe M', all substantially as described.

6. The combination, with the boiler having tubes G and H, of the arch K,lining I, pipe L', andl fan L, all substantially as described.

7. The combination, in a boiler having tubes G and H, of the archK,having openings k, the lining I, having damper i, the exhaust I,damper e, fan L, and pipe L', all substantially as described.

8. The combination, in a boiler, of the direct tubes G, smoke-box J,return-tubes H, partition F, and feed-pipe a, located near the exit endof said tubes H, as described, and for the purpose set forth.

In testimony whereof I have hereunto set my hand this 2d day of June,1885.

AMAsA C. PAUL, C. N. DICKEY.

